Did you know?
Circumference of Neptune (154,600 km) is 40 thousand x Depth of the Mponeng Gold Mine (South Africa) (3.9 km)
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Fastest speed attained by a manned rocket aircraft (7,270 km/h)
Yes, there's now a book based on these numbers. Oxford University Press: July 2018.
Click here to learn more about it.
Click here for Podcast: Andrew Elliott interviewed for New Books Network.